Exemplary embodiments of the invention generally relate to rotary wing aircrafts, and more particularly, to a rotor hub and shaft of rotary wing aircraft.
A helicopter rotor hub is the primary structural assembly for driving torque to each rotor blade, balancing centrifugal loads between opposing rotor blades, and transferring lift loads to the aircraft fuselage. Conventional rotor hub assemblies require a plurality of cones to center the rotor hub, a large shaft nut to retain the hub at the end of the rotor shaft, and additional components to prevent loosening of the shaft nut during operation of the rotary wing aircraft. Although these systems perform adequately, it is always desirable to reduce the empty weight of the helicopter.
In addition, a counter-rotating rotary wing aircraft has controls and components, such as pitch control rods for example, arranged within the hollow interior of the upper rotor shaft. When a conventional rotor hub is used in the counter-rotating rotary wing aircraft, a large opening is generally machined into the hub to provide access and/or visual inspection of the components within the upper rotor shaft.